Answer:
It wouldn't be able to migrate to the cell's poles.
Explanation:
During anaphase, microtubules attach the chromosome's centromeres and start dragging them towards the poles of the cell. In mitosis, this causes the separation of both sister chromatids for each chromosome, and each chromatid migrates to a different pole. In meiosis, first each homologous chromosome is separated by the same process, and then the sister chromatids are separated during anaphase II. If a chromosome doesn't have centromeres, microtubules are unable to attach the chromosomes, and so the separation of either sister chromatids or homologous chromosomes can't take place.
Hairs are mostly fibrous proteins and are composed of keratin, and also the main constituent of skin, nails, wool, woof, feathers etc.
Keratin is the essential fibrous protein which has a structural and protective functions in the epithelium.
Answer:
The answer is:
D. the radiation of herbivores such as grazing animals
Explanation:
Oligocene and Miocene Epochs:
- The Oligocene epoch is characterized by temperate and subtropical climatic conditions which favored the expansion of grasses and reduced forest cover.
- The Miocene epoch, which succeeded the Oligocene era, is attributed to changes in global circulation due to global warming of the climate followed by global cooling towards the end.
The Oligocence and Miocene epoch are both attributed to the expansion of grasslands and savannah. Both eras marked rapid and drastic evolutionary changes in grazing mammals and herbivores. Diverse groups of grazing mammals lived throughout these eras. For example, the largest herbivore and land mammal of all time, <em>Indricotherium</em> (a sort of giant hornless rhinoceros), was present in the Oligocene era.
Similarly, the Oligocene era in North America favored the rapid radiation of primitive horses.
Answer: Which macromolecules from the mystery food sample will help you figure out who was guilty of making a mess in the classroom
Explanation:
Question:
A population of organisms is represented by three black marbles and three gray marbles. The gray organisms have a beneficial genetic mutation. Draw a model that shows natural selection over three generations of these organisms
Answer:
lThe population will suffer Directional selection. In the attached files you will find the drawing of the model.
Explanation:
Natural selection is the result of the phenotype-environment interaction which determines gene destiny in space and time, selecting beneficial alleles and increasing their frequency in the population. Among other types of natural selection, we can find the directional selection.
Directional selection increases in the proportion of individuals with an extreme phenotypic trait, in this case, the color of the organisms. This selection presents more frequently in those cases in which interactions between living organisms and the environment modify in the same direction.
Directional selection leads to the fixation of the beneficial allele and the consequent loss of the other one. In this case, for example, the gray suffered a beneficial mutation, and after three generations the allele codifying for this mutation shows an increase in its frequency, approaching fixation.
